Process of coating paper.



C. M. GAGE, JR.

PROCESS OF COATING PAPER.

APPLICATION FILED NOV. 12. ms.

Patented. Oct. 22, 1918.

Invenfor.

Charms M. Gage. Jr.

ATM/5.

\ ens-n, m, or nasr r'nnrnnnnn, MASSACHUSETTS.

raocnss or coarme rarna.

meat.

Specification of Letters Iatent,

Patented that. 22, acre.

Application filed November 12, 1915. Serial No. 81,182.

To all whom it may concern:

Be it known that I, CEARLns M. GAGE, J r.,

'a citizen of the United States, residinsg at tate etc, with a hard, lazed, smooth surface is to pass the pa or t rough a bath of coating material whic is preferably some clay compound, and then pass the coated paper through squeeze rolls whichdetermine the amount of coating to be left on the paper and then subject the paper to the action of brushes which operate on the coated surface thereof and have "for their purpose to spread the coating evenly. The paper is then dried in some suitable way and subsequently subjected to the calendering operation to give the surface the final pollsh.

Sometimes the paper is given a second coating of the finishing material so as to provide a better surface, but so far as I am aware,the second coating has always been applied after the paper has been dried so that theapplication of the second coating involves the same manipulation of the paper as the application of'the first coating does. The placing of two coatings on the paper thus doubles the labor and cost involved in applying one coating and correspondingly increases the cost of manufacture.

My invention comprehends a novel which a second coating can be apfirst coating is being applied, thus avoiding the necessity of a double manipulation of the paper and the consequent added labor cost.

coatings can be applied to the paper thereby giving it a superior finish at substantially the same iahor cost asthat involved in ap- Tn accordance with my method the two.

plying a single coating to the paper. In

carrying out my invention I apply a primary coating of finishing material to the paper, preferably by passing the paper through a bath, and then I pass the paper through squeeze rolls which determine the amount of coating to remain on the paper and also operate to force the coating more or less into the pores of the paper and thus fill the surface thereon. The paper is then subjected to the action of usual brushes by which the coating is evened up on the surface and the paper is then subjected to a drying action suflicient to partially dry 1 the coating. The aper is then acted upon for the purpose 0 still further evening up the coating that is applied thereto so asto prevent any wavy formation in the coating which mi ht be due to the shrinkage of the paper in the drying operation. I then apply. the second or finishing coating to the surface of the paper by means of a spray and in such a Way that the second coating-is evenly a plied over the smooth primary coating. y using a spray for applying the second coatlng it is ossible to apply a secand coating of any esired thickness and to apply it absolutely uniformly over the surface of the paper. The second coating is then subjected to a brushing action and the paper may then be passed to the usual suc-. tion apron and onto the usual drying apparatus where it is completely dried. With my invention it is possible to apply the second coatin during the same run as that in which the rst coating is applied so that the application-of the two coatings does not consume any more tiine than the usual operation of applying a single coating.

In order to give an understanding of my invention I have illustrated in the drawings diagrammatically an apparatus by which the method may be carried out, but I Wish to state that the invention is not limited to the apparatus shown;

In the drawing the paper to be treated is indicated at l and is shown as being taken from a roll 2. 3 is a bath of coating material through which the paper 1 is passed. This may conveniently bedone by. passing the paper over a direction r0114 down into the bath and arcund a roll 5. t designates these squeeze rolls isto coating which is applie also to press thelcoating material into the we: mam

squeeze rolls between which the paper is passed as it leaves the bath; The purpose of gage the amount of to the paper'and pores of the surface of the paper. 7 indi cates usualbrushes which act on the coated surface of the paper and which are reciprocated or vibrated in different directions for the purpose of evening the coating. Where the paper is coated on both sides, as shown in the drawings, these brushes will be placed to act on both sides of the paper.

The device as thus far described .issuch as is commonly used in coating paper.

From the brushes 7 the coated paper passes to a drying apparatus which partially dries the paper. This drying apparatus may convemently be a plurality of nozzles 8 arranged to blow heate air against the-paper and where the nozzles are situ ated on both sides of the paper as shown in the drawing, the paper will be floated between thenozzles and subjected to the drying .action of the air currents issuing from the nozzles. This drying of the paper sometimes shrinks it slightly with the result that the coating will have a more'or less wavy formation which would be detrimental to perfect printing. To correct this I. pass the paper while under slight tension over rolls 9 and 10 which are constructed with a perfectly smooth true surface and which are rotated with a surface s eed exactly corre spending to the speed 0 the paper. These r lls eliminate or correct any wavy'formation the'paper and insure that the paper as it leaves the ,rolls will be perfectly true and evenly coated. A second coating of coat ing material is then applied to the partiallydried paper by means of a spray, and for this purpose spray nozzles 11. are'shown. These spray nozzles may be of any suitable construction and are. adapted to spray an even coating of material onto one or both sides of the paper as desired, and they may be regulated to spray a coating of any desired thickness. This second coating is not pressed into the pores of the paper as-the first coating is, but merely hes on the'surface of the paper and is subjected to the ac 4 .tion of a single brush 12 to. assist in aneven A deposit ofthe coating. From the brush the paper passes-to the usual suction apron 13 and then into a drying apparatus of any usual formation where it is hung in festoons l i'and subjected to the drying action; 'After the paper is dried itmay be calendered and treated in the usual way. It will be noted that in my improved process both the mary and the secondary or finishing coating is applied to the paper during the same run, I thus obviat' any'separate manipulation of the paper.- he advantage of this is that a wavy formation produced in thed t single manipulation of the paper sufices for the apphca'tion of both coatings, and, there fore, both the labor cost and time involved coating were pressed into the pores of .the

aper. y p p While I have illustrated herein diagrammatically a machine for carryin out my invention, yet I wish to state that t e invention is not limited to any particular mechanism.

I claim: Y

1. The process of producing a smooth.

glazed surface on aper which consists in applying to the sur ace of the paper a main coating of the finishing material which produces the desired smooth. glazed surface, forcing said material into the pores of. the paper and spreading said material evenly over the surface ofthe paper, partially drying said material, passing the partially-dried coated face of the paper over a smooth-surfaced roll which rotates at the same surface speed as the speed at which the paper moves and at the same time causin the coated face of the aper to be .pressed lig tly agamst the roll wl iereby any wavy'formatlon resulting from the-partial drying operation is eliminated, then spraying onto the coated face of the partially dried paper a second coating of the same material as that of the first coating, and then drying the paper in any usual way.-

2. The-process of coating paper for the purpose of producting a smooth glazed surface thereon which consists in applying to a moving web of paper a primary coating of material adapted to produce a hard, smooth,

glazed surface, forcing said coating into the pores. of the paper, and spreadin said coating evenly over the paper, Sub ecting the coated paper to the action of drying blasts of air whereby the coating is parcoated surface of the paper to ehminate any .wavy formation, produced by the partial ing, and then applying to the. partially dried coated face of the papera light, evenly-spread second coating of the same material as that comprising the first coating and then drying the paperin any 'usual way.

recess of coating. paper 3. The p consists in applying to the paper a primary coating of finishing material adapted to produce a smooth, glazed surface onthe paper, partially drying: said jccating by subjecting it to the action of drying blasts of air, smoothing the coating while in its partially dried state so as to eate any .tially dried, smoothing the partially dried eraticinii theti spraying-a seeon&oeatin of the same finishing material onto the pri- 'mary eoating t. The proces'e of coating paper which consists in applying to the paper a primary coating of finishing material ada tegi to pro-- oromg. said coating into the pores of. the paper, p'arv, tially but notvcompletely drying said coatduce' a hard, glazed surface,

name to this specification,

blasts of an", spraying a second coating of the same finishing material onto the partially &ried surface of the paper and then drying the paper in any usual way;

. In testimony whereof I have i d my 15 

